Damping device for inflatable floats



July 4, 1967 J FRlTZSCHE 3,329,119

DAMPING DEVICE FOR INFLATABLE FLOATS Filed March 14, 1966 IN VENTORHERBERT J. FnrrzscHE Fig. 2. I

United States Patent 3,329,119 DAMPING DEVICE FOR INFLATABLE FLOATSHerbert J. Fritzsche, Dover, N.J., assignor, by mesne assignments, tothe United States of America as represented by the Secretary of the NavyFiled Mar. 14, 1966, Ser. No. 535,656 1 Claim. (Cl. 114-121) ABSTRACT OFTHE DISCLOSURE A stabilized floating device comprising an inflatable baghaving a plurality of spaced rows of inflatable tabs of flexiblematerial. The plurality of tabs are staggered in adjacent rows and eachtab is provided with a hole that provides an increased effectiveperipheral length.

The present invention relates to damping devices and more particularlyto damping devices for inflatable floats that are used for providingadditional buoyancy to structures, such as aircraft.

Various types of damping devices are known for attaching to floatingobjects to limit the amount of motion due to waves and Wind. Generally,these damping devices are comprised of vertical or horizontal platesthat are attached to a device and serve as fins. The present inventionrelates to improved damping devices for a flotation bag that are madeinternal with the bag and the damping devices deflate with the bag forstowage.

The damping device of the present invention consists of a plurality ofrows of tabs that are integral with a flotation bag that is to bedampened. Tabs in alternate rows are staggered and all the tabs areinflated with the bag which eliminates the complexity of a separateinflation system. The damping device is simple, compact, lightweight,and provides effective damping to a flotation bag.

It is therefore a general object of the present invention to provideimproved damping means for a flotation bag.

Other objects and advantages of the present invention will be readilyappreciated as the same becomes better understood by reference to thefollowing detailed description when considered in connected with theaccompanying drawing wherein:

FIGURE 1 is a partial side view showing a plurality of rows of tabs on aflotation bag;

FIGURE 2 is a bottom view of the devices shown in FIGURE 1;

FIGURE 3 is a partial perspective view showing a single tab attached toa portion of a flotation bag;

FIGURE 4 is a sectional view taken on line 4-4 of FIGURE 3; and

FIGURE 5 is a partial perspective view of a different embodiment of atab.

Referring now to the drawing, there is shown a flotation bag 11 which,by way of example, might be cylindrical in design and have hemisphericalends thereon.

3,329,119- Patented July 4, 1967 ice Flotation bag 11 might beconstructed of Nylon or Dacron fabric combined with a suitable elastomerso that the bag is both water-tight and air-tight. A plurality of rowsof tabs 12 are attached integral to flotation bag 11 so that the tabs 12are inflated upon inflation of bag 11. By way of example, five rows oftabs 12 are shown provided on bag 11, however, either a smaller orlarger number of rows might be provided without departing from the scopeof the invention. Also, by way of example, six tabs are shown in eachrow. Tabs 12 in adjacent rows are staggered, or alternately spaced, sothat a line passing the center of a particular tab will bisect thespacing between adjacent tabs in an adjacent row. This alternate spacingof tabs and also the spacing between rows of tabs tends to minimize flowintereference effects.

As best shown in FIGURE 4 of the drawings, an orifice or opening 13 isprovided in bag 11 for each tab 12 and thus tabs 12 are inflated uponinflation of bag 11. In FIGURE 5 of the drawing there is shown a tab 12that is provided with a hole 14. It has been determined that the dragcoeflicient is a function of P /A ratio, where P is the total peripheryof the tabs and A is the area. Thus the addition of hole 14 in tab 12 isan effective means of further increasing the ratio of P /A.

It can thus be seen that the present invention provides an improvedclamping device for a bag that is to be attached to a floating object.The multi-tab configuration is simple, compact, and lightweight, and itsrelative value of P /A makes it an efiective damper. The tabs areinflatable with the bag and thus there is eliminated the complexity of aseparate inflation system.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is to be understood,that within the scope of the appended claim, the invention may bepracticed otherwise than as specifically described.

What is claimed is:

A device for providing stabilized support for a floating structurecomprising:

an elongated inflatable bag of flexible material,

a plurality of spaced rows of inflatable tabs of flexible materialattached to the outer periphery of said inflatable bag, each said tabbeing provided with a through hole whereby the effective peripherallength of each said tab is increased, and wherein said tabs in adjacentrows are staggered; and

a plurality of openings connecting the inside of said inflatable tabs tothe inside of said tabs whereby said tabs are inflated upon inflation ofsaid bag.

References Cited UNITED STATES PATENTS 2,914,779 12/ 1959 Walker 9113,224,401 12/1965 Kobus 114-126 X MILTON BUCHLER, Primary Examiner. T.M. BLIX, Assistant Examiner.

